A standard luggage latch has a housing mounted on the piece of luggage and a latch body or slide displaceable in the housing between a latched and unlatched position and engageable only in the latched position with a latch component on the luggage lid to retain the latch component. A slide button fixed to the latch body is longitudinally displaceable on the housing between a forward position corresponding to the latched position and a back position corresponding to the unlatched position. A plurality of number wheels rotatable on the housing are associated with respective rotatable members and formations can engage between the members and the latch body to prevent movement of the latch body into the unlatched position except when the wheels are in a predetermined angular position. Respective couplings between each of the wheels and the respective member are movable between a coupled position for joint rotation of each member with the respective wheel and a decoupling position for rotation of each member independently of the respective wheel. A coding element connected to the couplings is displaceable between a coded position setting the couplings in the coupled position and a coding position setting the couplings in the uncoupled position.
Thus the coding element is actuated to allow a new combination to be set. The item carrying the latch is supplied to the user with a standard combination, normally 0-0-0, and the user can thereafter reset the combination to his or her own number. At a later date the user can even reset the combination. It is therefore necessary that this coding element be accessible enough that it is relatively simple for a person to actuate it to reset the combination, but not so accessible that it can be accidentally actuated and allow the combination to be accidentally reset.
In German patents 2,828,057 and 2,830,091 of Peter Milles the coding element is exposed on the inside of the latch housing, which in turn is exposed on the inside of the piece of luggage. Thus it is possible for the contents of the luggage to actuate this element and allow the combination to be reset inadvertently, leaving the user with a locked bag and no knowledge of the new combination. Alternately some form of protection for this element must be provided inside the bag, increasing costs to make the luggage.
German patent 2,816,073 of Lazlo Bako (based on U.S. application 855,602 filed 29 Nov. 1977) has a coding element which is covered by the latching component, typically a tongue, when the latch is closed, and which can be actuated only when the catch button is further depressed. When the latch is opened this element is exposed in the hole in the latch housing into which the eye of the latch tongue fits. This element is therefore exposed whenever the luggage is open, leaving considerable time for accidental actuation. In addition it is fairly obviously exposed and can be operated relatively easily by anyone even vaguely familiar with the latch with no need of tools.
Other systems are described in German patent 2,946,09I of Peter Milles and German patent document 3,030,440 of Claudio Castiglioni (based on an Italian priority date of 07 Sept. 1979). In these arrangements the catch button is actuated in a particular nonstandard manner for resetting the code. Unfortunately these procedures are just the type of thing that someone checking out the luggage in a showroom, for example, might do, so that the combination gets reset to a new unknown combination, making the luggage useless. The same thing can happen even if a child, for instance, plays with the catch. Although special inserts can be provided (see for example German patent 2,938,999 and German utility model 8,109,279) to prevent this from happening, this extra part once again complicates manufacture and adds to costs.